This invention relates to a technique for dynamically routing calls to and from individual telephone sets at a subscriber premises.
Presently, most subscriber premises, and particularly, residences and small businesses have each incoming telephone line hard-wired to an individual telephone set or to multiple telephones through a branch premises line. For a telephone set to receive calls on separate lines, each line must run to that set. Additionally, the telephone set must possess multi-line capability. Many residential subscribers initially commence service with a single telephone line and then add a second or even a third line at a latter time to accommodate teen-age children, to access the Internet via a dial-up connection, or to receive business calls. Similarly, a small business may commence service with a single line, and then add additional telephone lines as business expands. Most subscribers that add additional telephone lines do not wish to incur the cost of multi-line phones and the expense of running each additional telephone line to each multi-line telephone set.
Thus, there is a need for a technique for dynamically routing incoming calls to and outgoing calls from, different telephone sets to overcome the aforementioned disadvantages of the prior art.
Briefly, in accordance with the invention, there is provided a method for dynamically routing calls to and from each of a plurality of telephone sets at a subscriber""s premises to allow each set to receive or initiate a call on one of a plurality of incoming lines or their equivalent. On a continuous basis, the communications path to each telephone set is monitored for availability. When a call is received on a particular incoming line or equivalent, a check is made to determine which communication path (and which telephone set) is idle. Thereafter, a distinctive ringing signal is applied on each idle path. The ringing signal causes each telephone set on that idle path to generate a distinctive ring that is typically associated with the particular telephone line or equivalent on which the call was received. The idle communications paths are thereafter monitored to determine whether any of the telephone sets on an idle path have gone off-hook to answer the call, whereupon, the call is routed to the off-hook telephone set on the associated communications path. The remaining idle communications paths (i.e., the communications paths on which the telephone sets remain on hook) are released for future calls.
When a subscriber seeks to initiate an outgoing telephone call, the subscriber goes off-hook on a telephone set associated with a particular communications. The off-hook condition is detected and in response, the call initiated from the now-off hook telephone set is routed to an idle outgoing telephone line or equivalent. If the subscriber seeks to place that outgoing call on a particular outgoing line or its equivalent that is idle, then the call is routed on that particular line or equivalent.